Slack-adjuster for car-brakes.



No, 778,597. PATENTE D DEC. 27, 1904.

W. O. MUNDY.

SLACK ADJUSTER FOR OAR BRAKES.

APPLIOATION FILED MAR- 29. 1904.

PATENTED DEC. 27, 1904. W. O. MUNDY.

SLACK ADJUSTER FOR GAR BRAKES.

APPLICATION FILED MAR. 29. 1904.

2 SHEETS-SHEET 2- UNITED STATES Patented December 27, 1904.

ATENT FFICE.

SLACK-ADJUSTER FOR CAR-BRAKES.

SPECIFICATION forming part of Letters Patent No. 778,597, dated December 27, 1904.

Application filed March 29, 1904.. Serial No. 200,505.

To all whom it may concern;

Be it known that I, IVILLIAM O. MUNDY, a

citizen of the United States, residing in the city of St. Louis, in the State of Missouri, have invented certain new and useful Improvements in Slack-Adjusters for Oar-Brakes, of which the following is afull, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification.

My invention relates to an adjusting means for taking up the slack in car-brakes when the brake-shoes become worn, whereby the brakelevers automatically actuate a slack-take-up to enable the setting of the brake-shoes after they have become worn.

The invention consists in features of novelty hereinafter fully described, and pointed out in the claims.

Figure I is a side elevation of my slack-adjuster. Fig. II is a top view of the central parts of the brake-beams and brake-lever fulcrums, with the brake-levers shown in hori- Zontal section, taken on line II II, Fig. I. Fig. III is a top or plan view of the slack-adjuster. Fig. IV is an enlarged vertical longitudinal section taken through the slack-adjuster on line IV IV, Fig. III. Fig. V is an enlarged vertical longitudinal section taken on line V V, Fig. III. Fig. V1 is a vertical cross-section taken on line VI VI, Fig. V.

The wheels of a car-truck and the brakeshoe heads are shown in dotted lines at A B, Fig. I.

G represents parts of the transverse members of a car-truck frame.

1 and 2 designate yokes secured to the truckframe members O and projecting therefrom longitudinally of the truck in opposite directions.

The brake-shoe heads B are carried by the brake-beams 3, and these'brake-beams carry fulcrurns at and 4. (See Fig. II and dotted lines, Fig. I.)

5 is the main brake-lever, that is pivoted at 6 to the fulcrum 1 and the upper end of which operates in the yoke 1 and has united thereto the brake-rod 7. 8 is an auxiliary brake-lever that is pivoted at 9 to the brake-beam fulcrum a and is united at its lower end to the lower end of the main brake-lever by a connecting-rod 10. The upper end of the auxiliary brake-lever operates within the yoke 2.

11 designates a shaft that passes transversely through the yoke 2.

12 is a U-shaped rocker that is swingingly mounted on the shaft 11 and which extends both upwardly and downwardly from said shaft and is provided at its lower end with legs 18, in which is seated a cross-pin 14.

15 is an oscillating frame consisting of two parallel bars, each having one end pivotally connected to the rocker-legs 13 by the crosspin 1d. The opposite ends of said frame-bars are supported by a link 16, pivoted thereto by a cross-pin 17 and pivotally upheld through the medium of the supporting-pin 18, mounted in the yoke 1. The oscillating frame-bars are united intermediate of their ends by connecting-rods and sleeves 19. The main brakelever 5 is positioned between one of these connecting-rods and the link 16, and the auxiliary brake-lever is positioned between the other connecting-rod and the rocker 12.

2O designates a pair of ratchet-wheels that are integral with each other and mounted on the shaft 11, which passes through the rocker 12 and the arms of the yoke 2. On the inner faces of these ratchet-wheels are'annular shoulders 21, and extending inwardly in the hub of the combined ratchet-wheels is a groove 22.

23 is a chain one end of which is connected to the auxiliary brake-lever 8 at 24 and the other end of which is connected to the ratchetwheels by a cross-pin 25 passing therethrough.

26 represents pawls swingingly mounted on a rod 27, positioned in the upper end of the rocker 12 and having their free ends arranged in engagement with the teeth of the ratchetwheels 20.

28 represents pawls rockingly mounted on a rod 29, seated in the yoke 2 and having their free ends arranged in engagement with the ratchet-wheels 20. I

The said pawls 26 and 28 are united by contractile springs 29, which serve to hold both series of said pawls in engagement with said ratchet-wheels.

Itis to be noted in connection with the oscillating frame 15 and the rocker 12 that after the oscillating frame has been moved in the manner stated to take up slack the springs 29 in addition to their services to hold the pawls in engagement with the ratchet-wheels act to return the rocker and oscillating frame to their former positions, so that the main brakelever may be brought into engagement with the link 16 when occasion demands such engagement. IVhen this movement occurs, the rockers are limited in their oscillation by lugs 30 carried thereby, which engage the under side of the yoke 2, as seen in Figs. IV and V.

In the use of my slack-adjuster when the brake-shoes are to be set to the car-wheels and are in an unworn or only slightly worn condition the brake-levers are operated in the usual manner and the shoes are set to the wheels without the slackadjuster mechanism being affected in any manner, for the reason that only a limited movement of the brakelevers is necessary to set the shoes and one that is insufficient to throw the slack-adjuster parts into operation. \Vhen, however, the brake-shoes become worn, a greater travel of the brake-levers is necessary to carry them to the ear-wheels, and therefore the main brakelever is brought during such greater movement into contact with the lower end of the oscillating frame-supporting link 16, as indicated by dotted lines, Fig. IV, thereby moving said link and frame in the direction indicated by the arrow in said figure during the act of carrying the brake-beams toward the car-wheels. As a consequence the oscillating frame is oscillated to draw the lower end of the rocker 12 in the direction of movement of the frame and the upper end of the rocker is thrown in a contrary direction, as indicated by the arrow, Fig. IV, and causes the pawls 26, engaging the ratchet-wheels 20, to rotate said wheels. The chain 23 is therefore wound onto the hub of said wheels, between them, during which action the vertically-disposed chain-links ride into the groove 22, while the horizontally-disposed ehainlinks ride on the shoulders 21 of the ratchet-wheels. The upper end of the auxiliary brake-lever 8 is therefore drawn toward the ratchet-wheels, while the lower end of the lever is swung in a contrary direction and, through the medium of the connecting-rod 10, serves to impart like movement to the main brake-lever 5 to carry the brakebeams, their heads, and shoes closer to the carwheels, so that the brake-shoes may be set to the wheels With a more restricted movement of the brake-levers. The brake-shoesetting operation is thereafter continued in like manner as originally until such time as the shoes become sufliciently further reduced by wear to occasion actuation of the oscillating frame 15 in the same manner as that described to additionally take up the existing slack.

I claim as my invention 1. In a slack-adjuster for car-brakes, the combination with brake-levers, of an oscillating member with which one of said levers may engage, and take-up mechanism having connection with one of said levers and said oscillating member, said take-up mechanism consisting of a rocker, ratchet and pawl members associated with said rocker, a pawl supported independently of said rocker and members associated therewith, and a spring connecting said rocker pawl member and said last-named pawl, substantially as set forth.

2. In a slack-adjuster for car-brakes, the combination with brake-levers, of an oscillating member with which one of said levers may engage, a rocker having connection with said oscillating member, a pair of ratchetwheels loosely supported within said rocker, pawls carried by said rocker for engagement with said ratchet-wheels, pawls supported independently of said rocker for engagement with said ratchet-wh eels to prevent retrograde rotation thereof, and a flexible connection between one of said levers and said ratchetwheels, substantially as set forth.

3. In a slack-adjuster for carbrakes, the combination with brake-levers, of an oscillating member with which one of said levers may engage, a rocker having connection with said oscillating member, a pair of ratchetwheels loosely supported within said rocker, pawls carried by said rocker for engagement with said ratchet-wheels, pawls supported independently of said rocker for engagement with said ratchet-wheels to prevent retrograde rotation thereof, flexible connection between one of said levers and said ratchet-wheels, and springs connecting said rocker-carried pawls and pawls mounted independently of said rocker, substantially as and for the purpose set forth.

WVILLIAM O. MUNDY.

In presence of BLANOHE Hoe-AN, NELLIE V. ALEXANDER. 

